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Unicode to ASCII string conversion Messages   Related Types This message was discovered on microsoft.public.dotnet.languages.vb. Responses highlighted in red are from those people who are likely to be able to contribute good, authoratitive information to this discussion. They include Microsoft employees, MVP's and others who IMHO contribute well to these kinds of discussions. Post a new message to this list... Ger I have not been able to find a simple, straight forward Unicode to ASCII string conversion function in VB.Net. Is that because such a function does not exists or do I overlook it? I found Encoding.Convert, but that needs byte arrays. Thanks, /Ger Reply to this message...        Herfried K. Wagner [MVP] (VIP) * "Ger" <Click here to reveal e-mail address> scripsit: [Original message clipped] 'System.Text.Encoding.ASCII.GetBytes', 'System.Text.Encoding.Unicode.GetByte'. BTW: Notice that there is no 1:1 mapping defined between Unicode and ASCII, ASCII is 7-bit only and can thus only represent 128 characters. -- M S Herfried K. Wagner M V P <URL:http://dotnet.mvps.org/> V B <URL:http://dotnet.mvps.org/dotnet/faqs/> Reply to this message...        Ger "Herfried K. Wagner [MVP]" <Click here to reveal e-mail address> schreef in bericht news:%Click here to reveal e-mail address... [Original message clipped] forward string-to-string conversion. It is possible ofcourse to write a simple function to do this and using the encoding class, but I was just wondering why the framework does not support the "direct string-to-string". /Ger Reply to this message...        Cor Ligthert Ger, [Original message clipped] In the dotNet is a "String" is forever a string of unicode Chars. What you call "ascii string" is forever a bytearray. Therefore as an answer there is nothing more than Herfried suggested. Although you can create an array of objects which contains bytes, however that is no solution in my opinion. I hope this helps to get the idea? Cor Reply to this message...        Ger Ah, now I think I get the idea. So when I convert a (unicode) string into an ascii byte array, and then the byte array back into a string, I still have Unicode, right? So that is of no use when you want to write ASCII to a filestream. Is the code below then writing ASCII output to my filestream? Dim UnicodeString As String = "abcdëfg" Dim fsOutput as New FileStream(..) Dim wOutput As New StreamWriter(fsOutput, System.Text.Encoding.ASCII) wOutput.WriteLine(UnicodeString) Thank you for your reply. /Ger "Cor Ligthert" <Click here to reveal e-mail address> schreef in bericht news:eWAgM%Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Jay B. Harlow [MVP - Outlook] (VIP) Ger, [Original message clipped] ASCII. [Original message clipped] what is going to read the file again. I would recommend with an ANSI encoding (see below) or UTF8 encoding. With ASCII you will loose all extended characters (ASCII is 7 bit encoding), with ANSI you will loose characters that are outside of your regional ANSI code page. UTF8 preserves all Unicode characters. I would recommend ANSI encoding if the file was going to be opened by casual users in Notepad. I would recommend UTF8 if full Unicode support is required. ANSI & UTF8 are both 8 bit encodings. > Is the code below then writing ASCII output to my filestream? Yes that code is writing ASCII, as you included the ASCII encoding on the StreamWriter constructor. The text file itself will contain ASCII characters, when you subsequently open that text stream and read it (with a StreamReader) it will be converted back to Unicode strings. When reading the file back try to use the same encoding as written. For example if you wrote ANSI, then use ANSI to read. If you wrote UTF8, then use UTF8 to read. As ANSI & UTF8 encode characters 127 to 255 differently. Remember that Encoding.UTF8 is used on the stream writer if you do not give one, if you are reading text files created by Notepad, then you want Encoding.Default. I would recommend: > Dim wOutput As New StreamWriter(fsOutput, System.Text.Encoding.Default) Which will write the file in your current ANSI code page as defined by the regional settings in Windows Control Panel. Which will preserve extended characters. Remember that ANSI is an 8 bit encoding that is dependent on region (code page). While ASCII is a 7 bit encoding, ASCII does not support extended characters such as ë. It will be converted into either a normal e or a ?. Hope this helps Jay "Ger" <Click here to reveal e-mail address> wrote in message news:Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Ger Thank you very much guys for your help and clearing up the issue for me. I will go for Jay's solution and use ANSI 8-bit. /Ger "Jay B. Harlow [MVP - Outlook]" <Click here to reveal e-mail address> schreef in bericht news:%Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Jay B. Harlow [MVP - Outlook] (VIP) Ger, I should add that I would normally use Encoding.Default (ANSI) for straight text files. I would normally use UTF8 for XML files. Hope this helps Jay "Ger" <Click here to reveal e-mail address> wrote in message news:Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Ger Jay, Actually the reason I bothered this group with my question was because my app generates and writes HTML data to a file believing it would be interpreted by the browser as ASCII by setting charset=windows-1252 in the meta tag of the htlm head. Then I found that certain diacritical characters were not well interpreted by the browser, and I found that that was because of the characters in the generated stream were delivered as Unicode. After changing the meta tag in the HTML code to charset=UTF-8 all was fine, but it left me with the question on how these things work, hence why there was no simple string-to-string conversion in the framework. Your and Cor's replies made me understand better how these things work in ..Net, and I thank you both for your help in this. /Ger "Jay B. Harlow [MVP - Outlook]" <Click here to reveal e-mail address> schreef in bericht news:Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Jay B. Harlow [MVP - Outlook] (VIP) Ger, > interpreted by the browser as ASCII by setting charset=windows-1252 in the charset=windows-1252 is ANSI, not ASCII! If you use Encoding.Default you will (normally) wind up with windows-1252 in the US and some of Europe. Try the following: Debug.WriteLine(System.Text.Encoding.Default.EncodingName, "encoding name") Debug.WriteLine(System.Text.Encoding.Default.BodyName, "body name") Debug.WriteLine(System.Text.Encoding.Default.HeaderName, "header name") Debug.WriteLine(System.Text.Encoding.Default.WebName, "web name") Debug.WriteLine(System.Text.Encoding.Default.CodePage, "code page") Debug.WriteLine(System.Text.Encoding.Default.WindowsCodePage, "windows code page") I would expect Encoding.Default with charset = Encoding.Default.WebName should give you the effect you desire, with any regional settings. Of course UTF8 will preserve ALL unicode characters in your output (good for XML & HTML). Hope this helps Jay "Ger" <Click here to reveal e-mail address> wrote in message news:Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Cor Ligthert Jay, > If you use Encoding.Default you will (normally) wind up with windows-1252 in [Original message clipped] can see it is only not used in the Cyriclic writing European countries. See the link bellow And I miss even some languages on that as from Kroatia, Slovenia (Miha), Slowaaks and I am in doubt about Turkish So probably European countries which not uses 1252 are where is spoken Greek Rumanian (retroromanish is one of the 4 in Swiss spoken languages) Serbians, Hertza/Bosnie, Russian Look at the bottom of the page, the page is in German however I think easy to understand http://de.wikipedia.org/wiki/Windows-1252#Windows-1252 So next time you can in my opinion write "most European" I hope this gives again some ideas Cor Reply to this message...        Jay B. Harlow [MVP - Outlook] (VIP) Cor, Aren't some of the European countries one of two encodings, such as the Netherlands? Or is that just the DOS code page? (Trying to remember something I thought you've stated before). Jay "Cor Ligthert" <Click here to reveal e-mail address> wrote in message news:Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Cor Ligthert Jay, Therefore I checked it, I have confused you where I was talking about the DOS 437 and 850 code page and you never knew what was used, however we use now probably all the 1252. Cor [Original message clipped] Reply to this message...        Cor Ligthert br................ [Original message clipped] That "you" never knew is not Jay, just as saying. Reply to this message...        Cor Ligthert Jay, Because of Ger's answer, now I become curious. I did not read it in your message, however what is the solution, Ger told he wanted a straight string to string conversion and explicitly no bytearray, however now I understand he can convert Unicode to a 8 bits ANSI String in VBNet? (And I am not talking about writing a file with 8 bits chars by decoding the char) I showed in this thread with a link to an MSDN page that a String contains forever 16 bits Chars. Is that documentation wrong or do I not understand it or maybe even something complete different.. Cor "Jay B. Harlow [MVP - Outlook]" <Click here to reveal e-mail address> schreef in bericht news:%Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Jay B. Harlow [MVP - Outlook] (VIP) Cor, Read my post. ;-) I only discussed reading & writing strings to ASCII, ANSI, and UTF8 files (7 & 8 bit encodings). You are correct System.String & System.Char are UTF-16 (16 bit Unicode), files can be ANSI, ASCII, UTF7, UTF8, EBCDIC, UTF16 and many other encodings. FWIW: VS.NET 2005 (.NET 2.0, aka Whidbey, due out in 2005) appears to support UTF-32 encoding for files. http://msdn2.microsoft.com/library/ts575t62.aspx Hope this helps Jay "Cor Ligthert" <Click here to reveal e-mail address> wrote in message news:%Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Cor Ligthert Ger > Ah, now I think I get the idea. So when I convert a (unicode) string into an [Original message clipped] That I do not say, however when you read it back in a String you have again a string of Chars. http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemcharclasstopic.asp I hope this helps? Cor Reply to this message...        Jay B. Harlow [MVP - Outlook] (VIP) Ger, In addition to Herfried's comments. For information on Unicode, ASCII and Encoding in .NET see: http://www.yoda.arachsys.com/csharp/unicode.html The samples may be in C#, however they should easily be converted to VB.NET Hope this helps Jay "Ger" <Click here to reveal e-mail address> wrote in message news:up$Click here to reveal e-mail address... [Original message clipped] Reply to this message...        Ger Thanks Jay, a most useful document. /Ger "Jay B. Harlow [MVP - Outlook]" <Click here to reveal e-mail address> schreef in bericht news:Click here to reveal e-mail address... [Original message clipped] Reply to this message...     System.Char System.Diagnostics.Debug System.IO.FileStream System.IO.StreamReader System.IO.StreamWriter System.String System.Text.Encoding Ad MBR BootFX Best-of-breed application framework for .NET projects, developed by Matthew Baxter-Reynolds and MBR IT

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